Electrical cords connect to power sources through male plugs into female electrical sockets, and electric cords can be extended through a female connector of one cord connecting to a male plug connector of another cord. However, electrical cords are sometimes hung or installed in reverse, or the electrical cord connectors may get damaged and require replacing. For example, outdoor Christmas lights can accidently be installed in reverse, with the male plug furthest away from the intended power source, requiring either a long extension cord to connect the male plug end to the power source, or the lights to be taken down and reinstalled in the other direction, with the connectors in the correct position. An unsafe option is to remove the female connector end, installing a male plug in its place, and then plugging into an outlet, creating a very dangerous electrical hazard at every male connection, and at the exposed prongs of the male plug at the opposite end of the lights.
The contents of all of these patents and published applications are hereby incorporated by reference. Various modifications and combinations have been envisaged for electrical plugs, receptacles, adapters and combinations therein, as set out in U.S. Pat. Nos. 5,232,381, 4,904,195 and U.S. Pat. No. 7,029,312 describes an electrical cord with a male plug at both ends, for use when an electrical cord or a string of lights ends in a female connector at the electrical outlet, instead of a male plug.